Specific sensitivities or general vulnerability? Trigger beliefs moderate acquisition and generalization of symptom expectancies

Abstract

Background: Beliefs about allergic triggers often do not match objective trigger tests, which may be due to generalization of trigger beliefs to conceptually/perceptually similar triggers. In this study, we aimed to reduce overgeneralization of triggers, by manipulating information about the mechanisms of allergy triggers prior to participation in a trigger-learning task. Methods: Healthy participants (N=48) received information that allergic reactions were a result of specific sensitivities versus general allergic vulnerability, and performed a trial-unique trigger acquisition task. CO2 was used to induce symptoms, and CS’s either shared (e.g. birds-mammals) or differed (e.g. birds-fungi) in category membership. During Acquisition, participants reported symptom expectancy and symptom intensity for all triggers. One day later, participants rated symptom expectancies for old and novel CS+/CS- triggers, and for exemplars of novel trigger categories. Data were analysed using multi-level models. Findings: Only a subgroup of participants (n=22) showed differences between CO2 and room air symptoms. These participants showed differential CS+/CS-symptom expectancies (t(1920=3.12, p=.002), which were moderated by information and CS category relationships (F(1,1920)=7.01, p=.008): general vulnerability information led to increased CS+/CS- differentiation when CS’s shared category membership, whereas information about specific sensitivities increased CS+/CS- differentiation when CS’s did not share categories. Furthermore, information about specific sensitivities reduced generalization to novel trigger categories (F(4,3820)=17,08, p<.001). Discussion: Prior information about the mechanisms of allergic disease has an impact on the development and generalization of trigger beliefs. However, interactions between prior information and other characteristics of the learning task suggest difficulties in translating these findings into clinical applications.